This invention relates to a new and useful method for stabilizing labile organic reagents which are prone to hydrolysis in aqueous media and which are stable in organic media. This includes coenzymes and other organic compounds, but excludes enzymes because they denature in 100% organic solvents. The organic reagents can be of biological origin or can be synthesized.
It has been estimated that 25% of all in vitro diagnostic tests conducted annually in the United States are not reliable. Unreliable tests can result in unnecessary medical treatment, the withholding of necessary treatment and lost income. Because of their high specificity, the use of enzyme determinations has significantly increased during the last few years, and indications are that this trend will continue. However, rigorous quality control measures are required to assure the accuracy and consistency of results. This requirement stems from the fact that the exact nature of enzymes, as well as the mechanisms of their action, remain unknown for the most part.
At present, the most important reason for the unreliability of in vitro diagnostic tests is the instability of the aqueous solution of the organic reagents used. Current methodologies require the use of numerous labile reagents. Due to this problem, rigorous quality control in the manufacture of in vitro diagnostic kits is required, and this quality control is, of course, costly. Moreover, if control in any step in the process is not maintained within a high degree of control standards, the quality of the final product can be reduced materially.
The present commercial state-of-the-art used for stabilizing the reactive ability of coenzymes and other organic reagents is by locking them into a solid matrix by: (a) freeze drying; (b) dry blending such as used for tableting dried powders in the pharmaceutical industries; or (c) by chemical immobilization of the reagent. Contrary to the sophistication these terms imply, these approaches are impractical and expensive. A manufacturer is forced to remove the water and supply a partial product, thus relinquishing part of the quality control cycle to the user who must dilute the final product. Laboratories are forced to pay the high cost of freeze drying and dry blending, and much reagent is wasted due to poor dilution techniques by unsophisticated laboratory personnel. Furthermore, only limited packaging modes and sizes are available.
Therefore, there is a need for a method for stabilizing labile, hydrolysis prone organic reagents in a liquid media so the reagents can be provided in a single container with excellent shelf life, where the container can be repeatedly opened for use without substantial degradation of the organic reagent therein. The method for stabilizing the labile organic reagents in a liquid media must be able to be effected with relatively low-cost, commercially available stabilizing ingredients, and the method must be effective for stabilizing the reagents in the presence of other labile reagents.